JP2013006577A - Camber controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sufficiently improve fuel consumption.SOLUTION: This controller includes: a vehicle body; a plurality of wheels; a camber varying mechanism for applying camber to a prescribed wheel; a processing means for determination of generation of oscillation which determines whether or not an oscillation is generated in the vehicle; and a camber application processing means for applying camber to the prescribed wheel when the generation of oscillation in the vehicle is determined. When the generation of oscillation in the vehicle is determined, since camber thrusts are generated in opposing directions to each other to respective tires of the prescribed wheels, the vehicle can travel with sufficient safety. The fuel consumption is sufficiently improved.

Description

  The present invention relates to a camber control device.

  Conventionally, in a vehicle, fuel consumption is improved by reducing the total weight of the vehicle, using tires with low rolling resistance, or controlling the vehicle according to road conditions.

  For example, when the vehicle is controlled according to the road surface condition, the road surface condition is calculated based on the road surface friction coefficient and the tire rolling resistance, and the vehicle is driven by the two-wheel drive system based on the calculation result. The vehicle can be driven by a four-wheel drive system (see, for example, Patent Document 1).

JP 2005-225282 A

  However, in the conventional vehicle, when the vehicle moves by a small amount through the tire depending on the road surface condition, and the vibration is generated in the vehicle, the driver makes the steering wheel minute in order to suppress the generated vibration. May be manipulated.

  As a result, since the vehicle cannot be run with sufficient stability, the fuel consumption cannot be sufficiently improved.

  It is an object of the present invention to provide a camber control device that solves the problems of the conventional vehicle and can sufficiently improve fuel efficiency.

  For this purpose, in the camber control device of the present invention, the vehicle body, a plurality of wheels rotatably arranged with respect to the body, and a predetermined wheel among the wheels are arranged. The camber variable mechanism for applying the camber, the vibration generation determination processing means for determining whether or not vibration is generated in the vehicle, and the vibration generation determination processing means are determined to be generating vibration in the vehicle. In some cases, the camber variable mechanism is operated to provide camber applying processing means for applying camber to the predetermined wheel.

  According to the present invention, in the camber control device, a vehicle body, a plurality of wheels disposed rotatably with respect to the body, and a predetermined wheel among the wheels are provided. The camber variable mechanism for applying the camber, the vibration generation determination processing means for determining whether or not vibration is generated in the vehicle, and the vibration generation determination processing means are determined to be generating vibration in the vehicle. In some cases, the camber variable mechanism is operated to provide camber applying processing means for applying camber to the predetermined wheel.

  In this case, when the vibration generation determination processing means determines that vibration is generated in the vehicle, the camber variable mechanism is operated and camber is applied to the predetermined wheel. Canvas rust is generated in the tires in directions opposite to each other.

  Therefore, it is possible to suppress the vibration from being generated in the vehicle, and the driver does not operate the steering wheel minutely.

  As a result, the vehicle can be driven with sufficient stability, so that fuel consumption can be sufficiently improved.

It is a control block diagram of the vehicle in the embodiment of the present invention. It is a conceptual diagram of the vehicle in embodiment of this invention. 1 is a perspective view of a camber system in an embodiment of the present invention. It is a front view of the camber system in an embodiment of the invention. It is a top view which shows the principal part of the camber system in embodiment of this invention. It is a main flowchart which shows operation | movement of the control part in embodiment of this invention. It is a figure which shows the subroutine of the high-speed driving | running | working judgment processing in embodiment of this invention. It is a figure which shows the subroutine of the vibration generation judgment process in embodiment of this invention. It is a 1st figure for demonstrating the change of the toe angle by the roll steer in embodiment of this invention. It is a 2nd figure for demonstrating the change of the toe angle by the roll steer in embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 2 is a conceptual diagram of the vehicle in the embodiment of the present invention.

  In the figure, 11 is a body that is a vehicle body, 12 is an engine as a drive source, WLF, WRF, WLB, and WRB are arranged on the left front, right front, and left rear that are rotatably arranged with respect to the body 11. And wheels WLF, WRF, WLB, WRB are provided with a wheel (not shown) formed of an aluminum alloy or the like, and a tire 36 that is fitted to the outer periphery of the wheel. .

  The wheels WLF and WRF constitute a driving wheel and a front wheel, and the wheels WLB and WRB constitute a driven wheel and a rear wheel. The wheels WLF and WRF constitute the left and right front wheels, and the wheels WLB and WRB constitute the left and right rear wheels.

  The vehicle has a front-wheel drive structure, and the engine 12 and wheels WLF and WRF are connected via a drive shaft 46 as a transmission shaft. Then, the rotation generated by driving the engine 12 is transmitted to the wheels WLF and WRF, and the wheels WLF and WRF are rotated.

  In the present embodiment, the vehicle has a front wheel drive structure, but the wheels WLB and WRB function as drive wheels, the rear wheel drive system, and the wheels WLF, WRF, WLB, and WRB are drive wheels. It is also possible to have a structure such as a four-wheel drive system that functions as: In addition, the vehicle includes an engine 12, but a drive motor is provided as a drive source, and rotation generated by driving the drive motor is transmitted to wheels that function as drive wheels. An engine and a drive motor are disposed as drive sources, and rotation generated by driving the engine and drive motor can be transmitted to wheels functioning as drive wheels. Furthermore, a wheel motor can be disposed on a wheel that functions as a driving wheel, and the wheel can be directly rotated by rotation generated by driving the wheel motor.

  Reference numeral 13 denotes an operation unit for a driver who is an operator to steer the vehicle, and a steering wheel as a steering member. Reference numeral 14 denotes an operation unit for the driver to accelerate the vehicle. An accelerator pedal 15 as an acceleration operation member is a brake pedal as an operation unit for the driver to brake the vehicle and as a braking operation member.

  By the way, in the present embodiment, a predetermined negative camber θ can be applied to a predetermined wheel among the wheels WLF, WRF, WLB, and WRB, and in the present embodiment, the wheel WLB and WRB. It has become.

  Therefore, as a camber variable mechanism for imparting camber θ to each wheel WLB, WRB or canceling imparting camber θ to the wheels WLB, WRB between the body 11 and each wheel WLB, WRB. Actuators 31 and 32 are provided.

In the normal state in which the actuators 31 and 32 are not operated, that is, the initial state, the wheels WLB and WRB are provided with a camber having a predetermined angle defined by the vehicle specifications, that is, a reference camber α as necessary. The Therefore, in the present embodiment, a predetermined camber is added to the reference camber α, and the camber θ is
−5 [°] ≦ θ <0 [°]
To be. When the reference camber α takes a negative value, the predetermined camber is added to the reference camber α, and the absolute value of the camber θ is increased.

  In the present embodiment, the actuators 31 and 32 are arranged between the body 11 and the wheels WLB and WRB. However, the actuators are arranged between the body 11 and the wheels WLF and WRF. Or an actuator can be disposed between the body 11 and the wheels WLF, WRF, WLB, WRB.

  Next, the structure of a camber system for operating the actuators 31 and 32 will be described. In this case, since the structures of the camber systems of the wheels WLB and WRB are the same, only the actuator 32 on the wheel WRB side will be described.

  3 is a perspective view of the camber system according to the embodiment of the present invention, FIG. 4 is a front view of the camber system according to the embodiment of the present invention, and FIG. 5 is a plan view showing the main part of the camber system according to the embodiment of the present invention. FIG. 3 and 5, arrow A represents the front of the vehicle.

  In the figure, WRB is a wheel, 21 is a wheel, 30 is a suspension device, 32 is an actuator, 36 is a tire, 38 is a hub for holding the wheel WRB, 39 is a disc brake as a braking element, and 43 is the hub 38. And a movable plate (hub support member) as a movable member that rotatably supports and swings the disc brake 39. The wheel WRB, the suspension device 30, the actuator 32, etc. constitute a camber system.

  The suspension device 30 includes first and second suspension members 101 and 102 disposed on the body 11, and a bracket 103 as a unit support member attached between the first and second suspension members 101 and 102. The upper arm 104 as the first connecting member, the first lower arm 105 as the second connecting member, the second lower arm 106 as the third connecting member, the spring 107 as the biasing member, the shock absorber 108, the tray A ring arm 109 and the like are provided.

  The actuator 32 includes a camber control motor 41 fixed to the bracket 103, the movable plate 43 swingably disposed with respect to the bracket 103, and a motor 41 for reducing the rotation of the motor 41. A speed reducer 44, a crank mechanism 45 connected to the speed reducer 44, rotated by receiving a rotation decelerated by the speed reducer 44, the crank mechanism 45 and the movable plate 43 are connected, and the crank mechanism 45 is rotated. The rotation angle of the upper arm 104 serving as a movement direction converting portion that converts the swinging movement of the movable plate 43 and the crankshaft 45a (shown divided into two in FIG. 5) constituting the crank mechanism 45, that is, An angle sensor 77 for detecting the crank angle is provided. The upper arm 104 is a common member that forms the suspension device 30 and the actuator 32.

  The speed reducer 44 is formed by a planetary gear mechanism, and includes a case 44a attached to the bracket 103, a ring gear 44R attached to the inner peripheral surface of the case 44a, and a first sun gear attached to the output shaft 41a of the motor 41. 44Sa, meshed with the ring gear 44R and the first sun gear 44Sa, and moved around the first sun gear 44Sa to be rotated, the first pinion 44Pa and the first pinion 44Pa being rotatable. A first pinion shaft 44b to be supported, a carrier 44CR which supports the first pinion shaft 44b and is rotated as the first pinion 44Pa moves around the first sun gear 44Sa, the carrier Second sun gear 44Sb attached to the center of rotation of 44CR, front A second pinion 44Pb meshed with the ring gear 44R and the second sun gear 44Sb, moved around the second sun gear 44Sb and rotated, and a second pinion shaft rotatably supporting the second pinion 44Pb. 44c, and an output member 44d that supports the second pinion shaft 44c and is rotated as the second pinion 44Pb moves around the second sun gear 44Sb.

  Therefore, when the motor 41 is driven, the rotation output to the output shaft 41a is decelerated and transmitted to the carrier 44CR, and the rotation of the carrier 44CR is further decelerated and transmitted to the output member 44d.

  The crank mechanism 45 is attached to the output member 44d on the same axis as the output shaft 41a of the motor 41, and is rotatably supported by the bracket 103, and the crankshaft 45a A crankpin 45b that is eccentric and rotated about the crankshaft 45a is provided, and the crankpin 45b and the upper arm 104 are rotatably connected.

  Therefore, when the motor 41 is driven, the rotation output to the output shaft 41a is decelerated by the speed reducer 44, and the crankshaft 45a is rotated as the output member 44d is rotated, and is connected to the crank pin 45b. The upper arm 104 thus moved is moved forward and backward, and the movable plate 43 is swung. As a result, a camber having an angle equal to the angle at which the movable plate 43 is tilted is applied to the wheel WRB. The crank mechanism 45 and the upper arm 104 constitute a lever crank mechanism.

  Further, the first lower arm 105 is connected to the first suspension by a connecting shaft (not shown) disposed at a predetermined part of one end in the horizontal direction, in the present embodiment, the end portion on the center side of the body 11. A camber shaft sh1 (connecting shaft) is rotatably connected to the member 101 and is disposed at a predetermined portion of the other side in the horizontal direction, in the present embodiment, the end of the body 11 on the wheel WRB side. The movable plate 43 is rotatably connected to the movable plate 43.

  The movable plate 43 is rotatably connected to the first lower arm 105 by the camber shaft sh1 at one end in the vertical direction, in the present embodiment, at a predetermined portion at the lower end. On the other side, in the present embodiment, the upper arm 104 is rotatably connected by a connecting shaft sh2 disposed at a predetermined portion at the upper end. Therefore, the movable plate 43 is swingably supported with respect to the body 11 and the bracket 103.

  The spring 107 is connected to the body 11 via a first spring receiver 107a at the upper end and is connected to the first lower arm 105 via a second spring receiver (not shown) at the lower end.

  The shock absorber 108 is connected to the body 11 at the upper end and to the first lower arm 105 at the lower end.

  Further, the second lower arm 106 is connected to the first suspension member 101 by a connecting shaft sh3 disposed on one side in the horizontal direction, in the present embodiment, at a predetermined portion of the center side end of the body 11. The movable plate 43 is connected to the movable plate 43 by a connecting shaft sh4 disposed at a predetermined portion of the wheel WRB side end of the body 11 in the present embodiment. And can be connected freely. The second lower arm 106 functions as a toe control link that adjusts the toe angle during alignment.

  Next, the vehicle control apparatus having the above-described configuration will be described.

  FIG. 1 is a control block diagram of a vehicle in an embodiment of the present invention.

  In the figure, 16 is a control unit as a first control device that controls the granting and releasing of camber, 19 is a vehicle control unit as a second control device that controls the entire vehicle, and 20 is a navigation device. , 61 is a ROM as a first storage unit, and 62 is a RAM as a second storage unit. The said control part 16 and the vehicle control part 19 comprise a computer, and perform various calculations and processes based on various data.

  Reference numeral 63 denotes a vehicle speed sensor as a vehicle speed detection unit that detects the vehicle speed v, and reference numeral 64 denotes a steering operation that detects a steering angle γ as an operation amount of the steering wheel 13 (FIG. 2) by the driver and as a steering amount. Steering sensor as a quantity detecting unit and as a steering quantity detecting unit, 66 is a lateral acceleration sensor as a first acceleration detecting unit for detecting a lateral acceleration gx which is a lateral acceleration of the vehicle, and 67 is a front and rear of the vehicle. A longitudinal acceleration sensor as a second acceleration detection unit that detects a longitudinal acceleration gy that is a direction acceleration, and a vertical acceleration sensor 68 as a third acceleration detection unit that detects a vertical acceleration gz that is an acceleration in the vertical direction of the vehicle. , 71 is an accelerator pedal depression amount (a) as an operation amount of the accelerator pedal 14 by the driver and as an acceleration operation amount. The accelerator sensor 72 as an accelerator pedal operation amount detection unit for detecting the cell opening degree ac and as an acceleration operation amount detection unit 72 is a brake operation amount as an operation amount of the brake pedal 15 by the driver. As a brake operation amount detection unit for detecting the brake pedal depression amount (brake stroke) br as a brake sensor as a brake operation amount detection unit, 73 is a stroke of each of the suspension devices 30 of the wheels WLB and WRB, That is, a suspension stroke sensor as a suspension detection unit that detects a suspension stroke ss, 75 is a load sensor as a load detection unit that detects a ground load fr applied to the wheels WLB and WRB, and 76 is a deformation allowance that is a deformation amount of the tire 36. That is, a tire collapse allowance sensor as a tire deformation amount detection unit for detecting the tire collapse allowance ε, 81 A yaw rate sensor as a yaw rate detector for detecting the yaw rate η of the vehicle, 82 is a roll rate sensor as a roll rate detector for detecting the roll rate ρ of the vehicle, and 83 is a pitch rate detector for detecting the pitch rate pr of the vehicle. The pitch rate sensor 84 is a camber sensor as a camber detection unit that detects the camber θ applied to the wheels WLB and WRB. In place of the steering sensor 64, a steering angle sensor for detecting a steering angle representing the inclination of the wheels WLF and WRF with respect to an axis extending in the longitudinal direction (front-rear direction) of the vehicle can be provided. In this case, the steering angle is set as the steering amount, and the steering amount detection unit is configured by the steering angle sensor.

  The suspension stroke sensor 73 is composed of a height sensor, a magnetic sensor, etc., the load sensor 75 is composed of a load cell (strain sensor) disposed in the suspension device 30, and the tire collapse allowance sensor 76 is A load cell (strain sensor) disposed on the tire 36 is used.

  The vehicle speed sensor 63, steering sensor 64, lateral acceleration sensor 66, longitudinal acceleration sensor 67, vertical acceleration sensor 68, accelerator sensor 71, brake sensor 72, suspension stroke sensor 73, load sensor 75, tire collapse allowance sensor 76, yaw rate sensor 81 , The roll rate sensor 82, the pitch rate sensor 83, the camber sensor 84, and the like, the body 11, the actuators 31, 32, the control unit 16, the vehicle control unit 19, and the wheels WLB, WRB constitute a camber control device. .

  The lateral acceleration sensor 66, longitudinal acceleration sensor 67, vertical acceleration sensor 68, yaw rate sensor 81, roll rate sensor 82, and pitch rate sensor 83 are disposed at the center of gravity of the vehicle.

  By the way, the road surface on which the vehicle is traveling has irregularities such as steps, protrusions, depressions, undulations, wrinkles, etc., and the irregularity causes the vehicle to move by a minute amount via the tire 36. If vibration occurs, the driver may slightly manipulate the steering wheel 13 in response to the generated vibration. In that case, the vehicle cannot be run with sufficient stability, and the fuel consumption cannot be sufficiently improved.

  Therefore, in order to make the vehicle run with sufficient stability and sufficiently improve fuel efficiency, it is conceivable to provide cambers to the wheels WLB and WRB when vibrations occur in the vehicle. When camber is applied to the wheels WLB and WRB, canvas rust can be generated in the opposite directions to the tires 36 of the wheels WLB and WRB, so that the vehicle can be driven stably and fuel consumption is sufficiently improved. can do. Further, depending on the structure of the suspension device 30, if a camber is applied to the wheels WLB and WRB, the toe angle of the wheels WLB and WRB can be changed by roll steer, so that the vehicle can be driven more stably. Fuel consumption can be further improved.

  It should be noted that camber is applied to the wheels WLB and WRB when the vehicle is more susceptible to vibration, such as during high speed travel, than when the vehicle is less susceptible to vibration, such as during medium to low speed travel. The effect by is high.

  On the other hand, when the canvas last is generated in the tire 36, the rolling resistance of the tire 36 increases accordingly, so it is necessary to reduce the running resistance and improve the fuel consumption so that the rolling resistance does not increase.

  For this reason, in the present embodiment, camber is applied to the wheels WLB and WRB when the vehicle is traveling at high speed and the road surface is uneven.

  Next, the operation of the control unit 16 for applying the camber θ to the wheels WLB and WRB and releasing the camber θ applied to the wheels WLB and WRB will be described.

  FIG. 6 is a main flowchart showing the operation of the control unit in the embodiment of the present invention, FIG. 7 is a diagram showing a subroutine of high-speed traveling determination processing in the embodiment of the present invention, and FIG. 8 is a vibration in the embodiment of the present invention. FIG. 9 is a first diagram for explaining a change in toe angle due to roll steer in the embodiment of the present invention, and FIG. 10 is a toe by roll steer in the embodiment of the present invention. It is the 2nd figure for explaining change of a corner.

  First, a determination information acquisition processing unit (not shown) of the control unit 16 performs a determination information acquisition process to give camber θ to the wheels WLB and WRB and to cancel camber θ to the wheels WLB and WRB. Therefore, in the present embodiment, determination information necessary for the vehicle, a vehicle state that represents the state of the traveling vehicle, and an operation state that represents the state of operation of each operation unit by the driver are acquired (steps S1 and S2).

  Therefore, the determination information acquisition processing means includes the vehicle speed sensor 63, lateral acceleration sensor 66, longitudinal acceleration sensor 67, vertical acceleration sensor 68, suspension stroke sensor 73, load sensor 75, yaw rate sensor 81, roll rate sensor 82, pitch. Upon receiving the sensor output of each sensor such as the rate sensor 83 and the camber sensor 84, the vehicle speed v, lateral acceleration gx, longitudinal acceleration gy, vertical acceleration gz, suspension stroke ss, ground load fr, tire crush margin ε, The yaw rate η, roll rate ρ, pitch rate pr, camber θ, and the like are acquired. The determination information acquisition processing unit acquires a signal from the navigation device 20 as a vehicle state.

  The determination information acquisition processing means includes, as a vehicle state, an acceleration or deceleration indicating a change rate (differentiation) of the vehicle speed v, a lateral acceleration change rate δgx indicating a change rate of the lateral acceleration gx, and the longitudinal acceleration gy. A longitudinal acceleration change rate δgy representing a rate of change, a vertical acceleration change rate δgz representing a rate of change of the vertical acceleration gz, a roll rate change rate δρ representing a rate of change of the roll rate ρ, and a pitch rate representing a rate of change of the pitch rate pr. It can also be obtained by calculating the change speed δpr or the like, or by calculating the roll angle based on the suspension stroke ss.

  Next, the determination information acquisition processing means receives the sensor output of each sensor such as the steering sensor 64, the accelerator sensor 71, the brake sensor 72, and the operation state includes the steering angle γ, the accelerator pedal depression amount ac, the brake pedal. The amount of depression br etc. is acquired.

  The determination information acquisition processing means includes, as an operation state, a steering angular velocity δγ representing a rate of change of the steering angle γ, a steering angular acceleration representing a rate of change of the steering angular velocity δγ, and a rate of change of the accelerator pedal depression amount ac. An accelerator pedal depression speed δac, an accelerator pedal depression speed δac ′ representing a change rate of the accelerator pedal depression speed δac, a brake pedal depression speed δbr representing a change rate of the brake pedal depression amount br, and the brake pedal depression speed δbr It can also be obtained by calculating a brake pedal depression acceleration δbr ′ representing the rate of change.

  Further, the determination information acquisition processing means acquires the steering angle of the wheels WLF and WRF as the operation state instead of the steering angle γ, or the steering angular speed indicating the change rate of the steering angle, and the change in the steering angular speed. It is also possible to acquire the rudder angular acceleration representing the rate.

  Subsequently, the control unit 16 determines the traveling state of the vehicle. That is, the high-speed traveling determination processing means (not shown) of the control unit 16 performs high-speed traveling determination processing, and determines whether or not the vehicle is traveling at high speed based on the high-speed traveling determination index (steps S3 and S4).

  Therefore, the high-speed travel determination processing means reads the vehicle speed v as a high-speed travel determination index (step S3-1), and the vehicle speed v is equal to or higher than the threshold value vth, and in the present embodiment, 60 [km / h] or higher, preferably Determines whether the vehicle is traveling at a high speed depending on whether it is 80 km / h or more (steps S3-2 and S3-3).

  In the present embodiment, it is determined whether the vehicle is traveling at a high speed depending on whether the vehicle speed v is equal to or higher than the threshold value vth. However, the average vehicle speed av during the past X [seconds] is determined. Whether or not the vehicle is traveling at high speed can be determined based on whether or not the threshold value is greater than or equal to the threshold value avth.

  Further, as a high-speed driving determination index, a signal indicating that the vehicle is traveling on a road where the vehicle can be driven at high speed, such as a highway, a toll road, or the like, that is, a high-speed driving road, that is, Then, it is possible to read a high-speed driving signal and determine whether the vehicle is driving at high speed based on the high-speed driving signal. In that case, the navigation device 20 detects the vehicle position of the vehicle by a GPS sensor (not shown) as a current location detection unit, and sends a high-speed travel signal to the control unit 16 when the vehicle position is on a high-speed travel path. The high-speed traveling determination processing means determines that the vehicle is traveling at a high speed when receiving a high-speed traveling signal, or receives the high-speed traveling signal and the vehicle speed v is equal to or higher than the threshold value vth. Determines that the vehicle is traveling at a high speed when the vehicle is traveling at a high speed, receives a high-speed traveling signal, and the average vehicle speed av during the past X [seconds] is equal to or greater than the threshold value avth. Can be.

  When it is determined that the vehicle is traveling at a high speed, the control unit 16 determines the road surface condition based on the vibration generation determination index for determining whether or not the vehicle is vibrating. Determine if the road surface is uneven.

  By the way, if the road surface is uneven, the vehicle moves through a small amount of time, in the lateral direction, in the front-rear direction, and in the up-down direction via the tire 36, and as a result, vibration is generated in the vehicle. Therefore, in the present embodiment, whether or not the road surface is uneven is determined based on whether or not vibration is generated in the vehicle.

  That is, a vibration generation determination processing unit (not shown) of the control unit 16 performs a vibration generation determination process to determine whether vibration is generated in the vehicle when the vehicle is traveling at high speed (steps S5 and S6).

  For this purpose, the vibration occurrence determination processing means acquires the lateral acceleration gx by reading it as a vibration occurrence determination index (step S5-1), and the lateral acceleration gx is equal to or greater than the threshold value gxth. [G] or more, preferably, whether or not vibration is generated in the vehicle is determined based on whether it is 0.1 [G] or more (steps S5-2 and S5-3).

  In the present embodiment, lateral acceleration gx is acquired as a vibration occurrence determination index, and the vibration occurrence determination processing means determines whether or not vibration is generated in the vehicle depending on whether the lateral acceleration gx is equal to or greater than a threshold value gxth. However, the longitudinal acceleration gy, the vertical acceleration gz, the yaw rate η, the roll rate ρ, the pitch rate pr, and the like can be acquired as vibration generation determination indexes.

  When the longitudinal acceleration gy is acquired as a vibration generation determination index, depending on whether the longitudinal acceleration gy is equal to or greater than a threshold value gyth, for example, 0.02 [G] or greater, preferably 0.05 [G] or greater. When it is determined whether or not vibration is generated in the vehicle and the vertical acceleration gz is acquired, the vertical acceleration gz is equal to or greater than a threshold value gzth, for example, 0.02 [G] or more, preferably 0.05 [G] or more. If the yaw rate η is acquired, whether the yaw rate η is equal to or greater than the threshold ηth, for example, ± 0.4 [° / s] or greater. Whether or not vibration is generated in the vehicle, and when the roll rate ρ is acquired, is the roll rate ρ equal to or higher than a threshold ρth, for example, ± 0.3 [° / s] or higher? Whether or not vibration is generated in the vehicle is determined, and when the pitch rate pr is acquired, whether the pitch rate pr is equal to or higher than a threshold value prth, for example, ± 0.2 [° / s] or higher. Then, it is determined whether or not vibration is generated in the vehicle. As the vibration occurrence determination index, two or more indexes among the lateral acceleration gx, the longitudinal acceleration gy, the vertical acceleration gz, the yaw rate η, the roll rate ρ, the pitch rate pr, and the like are acquired. It can be determined whether or not the vehicle is vibrating depending on whether or not each index is equal to or greater than a threshold value.

  Further, as described above, when the vehicle is vibrated, the rudder angle is changed by a small amount in the forward and reverse directions by the force applied to the wheels WLF and WRF via the tire 36 as described above. . In this case, the change in the steering angle is transmitted to the steering wheel 13 via a steering shaft (not shown), and the steering wheel 13 is rotated by a small amount in the forward direction and the reverse direction. In order to suppress a small amount of rotation, the steering angle γ of the steering wheel 13 is corrected.

  Therefore, the vibration generation determination processing means can acquire a frequency for correcting the steering angle γ of the steering wheel 13, that is, a correction frequency fγ, as a vibration generation determination index. For this purpose, the vibration occurrence determination processing means acquires the steering angle γ of the steering wheel 13 and calculates a correction frequency fγ based on the steering angle γ, and the correction frequency fγ is equal to or higher than a threshold value fγth, for example, 1 [Hz]. As described above, preferably, whether or not vibration is generated in the vehicle is determined based on whether or not the frequency is 2 [Hz] or higher.

  Further, the amount of rotation of the steering wheel 13 when the steering angle γ of the steering wheel 13 is corrected, that is, the correction amount εγ can be acquired as a vibration generation determination index. Therefore, the vibration occurrence determination processing means acquires the steering angle γ, calculates the correction amount εγ of the steering angle γ, and the correction amount εγ is equal to or greater than a threshold value εγth, for example, the steering angle γ is equal to or greater than 1 °. In addition, it is determined whether or not the vehicle is vibrating depending on whether the number of times n corrected for 2 [°] or less is 1 [times / second] or more.

When it is determined in the vibration occurrence determination process that vibration is generated in the vehicle, a camber application state determination processing unit (not shown) of the control unit 16 performs a camber application state determination process and the camber sensor 84. The detection camber θp, which is the camber θ detected by the
-5 [°] ≦ θp <0 [°]
Whether or not the camber θ is applied to the wheels WLB and WRB is determined based on whether or not (step S7).

  When the camber θ is given to the wheels WLB and WRB, the camber state holding processing means (not shown) of the control unit 16 performs the camber state holding processing to hold the wheels WLB and WRB in a state where the camber θ is given. (Step S8) When the camber θ is not given to the wheels WLB and WRB, the camber giving processing means as the first camber control processing means (not shown) of the control unit 16 gives the camber as the first camber control processing. Processing is performed, the actuators 31 and 32 are operated, and camber θ is applied to the wheels WLB and WRB (step S9).

In addition, if it is determined in the high-speed traveling determination process that the vehicle is not traveling at a high speed, or if it is determined in the vibration occurrence determining process that vibration is not generated in the vehicle, the camber application state determination The processing means reads the detection camber θp, and the detection camber θp
-5 [°] ≦ θp <0 [°]
Whether or not the camber θ is given to the wheels WLB and WRB is determined (step S10).

  When the camber θ is given to the wheels WLB and WRB, the camber release processing means as the second camber control processing means (not shown) of the control unit 16 performs the camber release processing as the second camber control processing. Then, the actuators 31 and 32 are operated to release the camber θ from the wheels WLB and WRB (step S11).

  If the camber θ is not applied to the wheels WLB and WRB, the camber state holding processing unit holds the wheels WLB and WRB in a state where the camber θ is not applied (step S12).

  As described above, in the present embodiment, when the camber θ is applied to the wheels WLB and WRB when vibration is generated in the vehicle, the tires of the wheels WLB and WRB are canvased in the opposite directions. Last occurs.

  Therefore, since it can suppress that a vehicle generate | occur | produces a vibration, a driver | operator does not operate the steering wheel 13 minutely.

  As a result, the vehicle can be driven with sufficient stability, so that fuel consumption can be sufficiently improved.

  The camber θ is applied to the wheels WLB and WRB when the vehicle is traveling at high speed, and the camber θ is not applied to the wheels WLB and WRB when the vehicle is traveling at medium and low speeds. It can be suppressed. Therefore, fuel consumption can be further improved.

  Further, since the canvas last is generated in the tires 36 of the wheels WLB and WRB so as to face each other, even if an external force is applied to the vehicle due to the unevenness of the road surface, the tire 36 of the wheel on the opposite side to the side where the external force is applied. A large canvas last is generated and the canvas last is applied to the vehicle as a restoring force. Therefore, the stability when the vehicle is traveling at high speed, that is, the traveling stability can be increased.

  As described above, when the vehicle is traveling at a medium or low speed, it is difficult to be affected by vibration, and it is less necessary to apply camber to the wheels WLB and WRB. Therefore, camber θ is applied to the wheels WLB and WRB. Absent.

  Therefore, when the vehicle is traveling at a low speed, the canvas 36 does not generate a canvas last, so that the rolling resistance of the tire 36 does not increase. As a result, fuel consumption can be sufficiently improved.

  By the way, when the camber θ is applied to the wheels WLB and WRB when vibration is generated in the vehicle, the toe angles of the wheels WLB and WRB are changed by roll steer depending on the structure of the suspension device 30.

  That is, when the movable plate 43 that supports the wheels WLB and WRB is attached to the trailing arm 109 as in the present embodiment, rolling occurs as the vehicle vibrates, and the trailing arm 109 is rotated and the wheels WLB and WRB are moved in the vertical direction. At this time, when the camber θ is applied to the wheels WLB and WRB, the toe angle changes.

  For example, as shown in FIGS. 9 and 10, when the vehicle is moving in the direction of arrow A, the vehicle is vibrated, and the trailing arm 109 is moved to the virtual stroke center sh5 (in the present embodiment). When the angle θs [°] is turned from the reference position in the direction in which the suspension stroke ss is reduced with the oscillation axis) as the oscillation center, the wheel WRB is moved in the direction of arrow B (upward). At this time, if camber θ is applied to wheel WRB, the toe angle of wheel WRB is changed to the toe-in side by the angle θt [°].

  Therefore, since it is possible to suppress the occurrence of vibration in the vehicle as the toe angle changes, the driver does not operate the steering wheel 13 minutely.

  Thus, depending on the structure of the suspension device 30, the vehicle can be driven more stably, and the fuel consumption can be further improved.

  By the way, when the vehicle is turned to travel, that is, when the camber θ is applied to the wheels WLB and WRB at the time of turning of the vehicle, the wheel on the outer peripheral side with respect to the turning center by centrifugal force (when turning the vehicle to the left) Is a wheel WRB, which is a wheel WLB when the vehicle is turned to the right.) A ground load applied to the inner peripheral wheel (a wheel WLB when the vehicle is turned to the left) is the wheel WLB. In this case, it is possible to increase the contact load applied to the wheel WRB.), The canvas last generated in the tire 36 of the outer peripheral wheel is changed to the canvas last generated in the tire 36 of the inner peripheral wheel. It can be made larger, and sufficient centripetal force can be generated in the vehicle. Therefore, stability during turning of the vehicle, that is, turning stability can be increased.

  Therefore, in the present embodiment, when turning the vehicle, it is determined whether or not the camber provision condition for turning is satisfied, and when the camber provision condition for turning is satisfied, the camber provision processing means includes the wheels WLB and WRB. Is applied to the camber, and the camber application condition for turning is not satisfied, the high-speed traveling determination processing means performs the high-speed traveling determination processing, the vibration occurrence determination processing means performs the vibration occurrence determination processing, and When the vehicle is vibrating at high speed, the camber imparting processing means imparts camber θ to the wheels WLB and WRB.

  In the present embodiment, the camber θ is imparted to the wheels WLB and WRB, so that the running stability and the turning stability are increased. Therefore, by reducing the loss tangent described later as the tire 36, A low rolling resistance tire in which rolling resistance generated by deformation of the tread of the tire 36 is reduced can be used, and fuel efficiency can be sufficiently improved.

  In the tire 36 using a low rolling resistance tire, the width of the tire 36 is made smaller than that of a normal (standard) tire, and the tread pattern which is a tread groove pattern is shaped so as to reduce the rolling resistance. At least the material of the tread portion is made to have a low rolling resistance.

  The loss tangent represents the degree of energy absorption when the tread is deformed, and can be represented by the ratio of the loss shear elastic modulus to the storage shear modulus. As the loss tangent is smaller, energy absorption due to deformation of the tread is reduced, so that rolling resistance generated in the tire 36 is reduced, and wear generated in the tire 36 is reduced. On the other hand, the greater the loss tangent, the more energy is absorbed by the tread, so the rolling resistance generated in the tire 36 increases and the wear generated in the tire 36 increases.

  The present invention is not limited to the above-described embodiment, and various modifications can be made based on the spirit of the present invention, and they are not excluded from the scope of the present invention.

DESCRIPTION OF SYMBOLS 11 Body 16 Control part 19 Vehicle control part 31, 32 Actuator 63 Vehicle speed sensor 64 Steering sensor 66 Lateral acceleration sensor 67 Longitudinal acceleration sensor 68 Vertical acceleration sensor 71 Acceleration sensor 72 Brake sensor 73 Suspension sensor 75 Load sensor 76 Tire collapse allowance sensor 81 Yaw rate sensor 82 Roll rate sensor 83 Pitch rate sensor 84 Camber sensor WLF, WRF, WBL, WRB Wheel

Claims (7)

The body of the vehicle,
A plurality of wheels arranged rotatably with respect to the body;
A camber variable mechanism that is disposed on a predetermined wheel of the wheels and that imparts camber to the wheel;
Vibration generation determination processing means for determining whether vibration is generated in the vehicle;
And a camber imparting processing means for actuating the camber variable mechanism and imparting camber to the predetermined wheel when it is judged by the vibration occurrence judging processing means that a vibration is generated in the vehicle. A camber control device.   The camber control device according to claim 1, wherein the vibration generation determination processing unit determines whether vibration is generated in the vehicle in accordance with an operation of the operation unit by an operator. While having judgment information acquisition processing means for acquiring the vehicle state representing the state of the running vehicle,
The vibration generation determination processing unit acquires the vehicle state acquired by the determination information acquisition processing unit as a vibration generation determination index. If the vibration generation determination index is equal to or greater than a threshold value, vibration is generated in the vehicle. The camber control device according to claim 1, wherein the camber control device is determined. While having a judgment information acquisition processing means for acquiring an operation state representing the state of operation of the operation unit by the operator,
The vibration generation determination processing unit calculates a vibration generation determination index based on the operation state acquired by the determination information acquisition processing unit. When the vibration generation determination index is greater than or equal to a threshold value, vibration is generated in the vehicle. The camber control device according to claim 1, wherein it is determined that the camber control device is present. Having a high-speed traveling determination processing means for determining whether the vehicle is traveling at a high speed;
The camber imparting processing means is determined by the high-speed traveling determination processing means to determine that the vehicle is traveling at a high speed, and the vibration occurrence determining processing means determines that the vehicle is vibrating. The camber control device according to any one of claims 1 to 4, wherein the camber variable mechanism is operated to apply camber to the predetermined wheel. While having judgment information acquisition processing means for acquiring the vehicle state representing the state of the running vehicle,
The high-speed travel determination processing means acquires the vehicle state acquired by the determination information acquisition processing means as a high-speed travel determination index, and determines whether the vehicle is traveling at high speed based on the high-speed travel determination index. Item 6. The camber control device according to Item 5.   The camber control device according to claim 1, wherein the predetermined wheel is a rear wheel.

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